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MBTcustom
06-13-2011, 01:14 PM
I honestly don't know where to post this question, so I decided to throw it on this table.
Does any body know if there are ideal ratios set forth for the ideal diameter of a diopter rear sight in relation to the distance from the eye (read "perceived diameter") in relation to the width of the front sight-blade? (Assuming that a blade is being used)
I only ask this because I have noticed over the years, that certain sight combinations are just easier to use than others. My very favorite sights that I have ever used where on a Winchester 290 22. They weren't too big or too small they complimented each-other very well and I could shoot gumballs off a tree at 100 yards. Maybe its just personal preference, but I notice that many older rifles that have factory peep sights, are just easier to shoot than rifles that have after market peeps installed. In my case, I re-barreled a no4 mk1 enfield and made a new front sight for it. I made the blade .050 inch wide. I am shooting it just fine, but it seems like my eye wishes the peep hole was smaller.
Any thoughts?

Doc Highwall
06-13-2011, 02:16 PM
The ideal TARGET aperture size is around .044" in full light conditions, and approximately 2"-2-1/2" from the eye, with the front post appearing to be as wide as the target or slightly wider.

For Hunting I would suggest .093' to .150".

You will be amazed how well you shoot with a larger front sight, and for a longer time as your eye does not get tired as fast.

When you break the shot with iron sights you should be focusing on the top of the front sight all the way through recoil, and over come the tendency to change your focus from the front sight to the target.

Tatume
06-13-2011, 03:15 PM
For shooting 1000 yard prone matches I install a blade that appears to fit between the sides of the target frame. Then I raise the sight until the top kisses the bottom of the bull and squeeze. Rear aperture diameter is chosen to suit the light conditions of the day, bigger on dark days and smaller on bright days.

Pepe Ray
06-13-2011, 03:41 PM
I'm constantly amazed at the lack if knowledge of the existence of the adjustable apertures offered by the Merit Sight Co.
Sight apertures for hunting, for target, threaded for various sight body's or designed to install directly to your shooting glasses.

A person's vision is unique to him and ONLY with youthful eyes can you safely gamble that the single aperture will satisfy in all shooting conditions.

Even with a pocket full of individually sized orifices you will soon tire of replacing them to fit the present conditions.

Yes, an adjustable camera type iris will cost more. So what!!

Good shooting to you.
Pepe Ray

303Guy
06-13-2011, 04:22 PM
My No4 has two apatures - one the larger preset main battle sight the other on the flip up with micrometer adjustment for range. The flip up aperture is smaller and will focus the front blade for me as I focus on the target. However, it forms an interferance pattern dark spot in the centre of the aperture. I don't know if that's a good thing or not. The larger aperture seems too large but in reality the eye automatically centres in an aperture and for quick aquisition it's fine.

I'm curious about focusing on the front blade - I don't do that. I can't. I like the aperture or 'semi-aperture' of a U-sight to focus or at least sharpen the front blade image. So for that I find there is an ideal blade width to U-notch width for a particular spacing and distance from the eye.

MBTcustom
06-13-2011, 04:23 PM
So the front sight and the rear sight have no relationship to each-other and are considered separate entities that perform totally different tasks? I apologize for my ignorance, but I am coming from a hunting point of view. Although I have a deep appreciation for precision, I have never participated in a rifle match of any kind. It makes sense that you would design the sights for the target you will be shooting, at the distance that the target will be shot at. But in a hunting situation, the target is an imaginary point somewhere in the middle of a game animal (fox sized all the way up to bear sized) at all different ranges and light conditions.
303guy has the heart of what I am saying. Its very hard to focus on the front sight when the target is not a constant factor ie. it can move. My rear sight is also the no4 mk1 configuration.

Larry Gibson
06-13-2011, 04:34 PM
The width of the front sight post sight is more dependant on the distance between the eye and front sight post/blade. One width can work just fine at one distance but not well at a closer (would appear wider) or farther distance (would appear narrower). The distance is usually controlled by the barrel length. The size of the aperture is dependant on light conditions to get a clear sharp focus on the tip of the front sight post. The adjustable Merit and Aunschutz are indeed very good to use with varying light conditions. However, when young your eyes can easily adapt to a wider range of aperture sizes.

Larry Gibson

BruceB
06-13-2011, 04:54 PM
The larger aperture on the #4 Rifle is called a "BATTLE SIGHT" for good reason. When the need is urgent or the range is close, that large aperture makes those fast, close-range shots easier. I used the as- issued battle sight on several close-range moose (under 50 feet) and it worked extremely well.

When time and range permit, the adjustable-range sight can be used to good advantage. However, I've never needed to use the feature when hunting as all my animals were well-within the capabilities of the battle sight.

I agree 100% with Pepe Ray concerning the Merit apertures. The one I have on my '03 Springfield has 13 positive "stops" to set the opening. For hunting, I just use the widest opening, but for load development etc., it is VERY valuable to be able to sharpen the sight picture on paper at various ranges and under different light conditions. My new-condition #4 Mk2 has a Parker-Hale match sight, the #5C. That sight has a P-H iris as well, which is much larger than the Merits. Its maximum aperture is over 1/4 inch,and it's still a very useful sight even at that extreme. It's REALLY valuable in poor light, such as dawn/dusk.

Regarding the Merit irises, be aware that different sight manufacturers use different thread specs for their interchangeable apertures. The Brownells' catalog has the information.

Doc Highwall
06-13-2011, 05:53 PM
I had a funny thing happen with a Merit sight once. I was at a 600 yard match shooting my shooting buddy's right handed rifle left handed because of being blind in my right eye. This is no problem just don't eject the case too fast or it will hit you in the face, ask me how I know. Well I had adjusted the aperture for the light conditions and had a sharp picture, but every couple of shots the sight picture went fuzzy. What was happening was my shooting coat was dragging on the rubber eye piece of the Merit every time I reach over to open the bolt with my left hand and was opening it to the max aperture. I wrote that down in my diary about shooting with the rubber on the eye piece.

When I shoot a hunting gun with a receiver sight I do all of the load development with a .048" aperture and I have a Williams Twilight Aperture that is .093" that I hunt with, and if it gets dark enough I will unscrew it and put it in my pocket until later when it gets light enough which is usually the next day.

303Guy
06-13-2011, 06:05 PM
I once made a ring rear sight replacement for the regular 'V' notch sight on my airgun (mounted in the same place). It was a thin wall piece of tube soldered onto a narrow mounting blade to give full view around the ring. The front sight was a ball on post type. It was great!

Von Gruff
06-13-2011, 07:01 PM
My rifles are for hunting so any target uses are suplementary.
For my 7x57 with a bolt mounted aperture that gives me about 3 1/2 inches of eye relief with the aperture ID of .116 and OD of .372 with the front blade at .098 for a 32in sight radius. Have kills out to 185yds on medium sized game.
My 404 has a bridge mounted aperture that I had a Merrit for but after I used it to set my loads on paper I removed it , (actually I sold it on), because of the large outer dia that I found restrictive in a hunting situation. The aperture is .110 ID and .382 OD with eye relief of 6 1/2 in and a front blade of .093 with a sight radius of 29 in.

These sights work very well for me with enough light for all conditions without to much OD to restrict view .

Von Gruff.

btroj
06-13-2011, 07:07 PM
I agree on the larger aperture for hunting. About .093 to .100 is good. Front sight is dependent on many things. I am assuming this is a hunting rifle so I would go wider. Need something that can be seen in lower light and that can be picked up fast.

This is a good time to learn to match the sights to the application. Good target sight can be lousy hunting sights. Hunting sights aren't always great target sights but they will still work.

Doc Highwall
06-13-2011, 07:24 PM
I like a front blade about .100" on my Marlin lever action rifles.
I am designing a scope mount for my 1895 Marlin that I cut the barrel down to 16.5" with a rear aperture peep built in, so if you take the scope off the peep sight will be there already. I will most likely make a new front sight also.

montana_charlie
06-13-2011, 09:18 PM
I honestly don't know where to post this question, so I decided to throw it on this table.
Yep. Your question has nothing at all to do with cast boolits, but now that the Shooter's forum is extinct we just have to wing it when picking a place to post something.
CM

XWrench3
06-13-2011, 09:23 PM
the only aperature sight that works well for me is one that has about a 9 power zoom to it. lol. old eyes just dont work like they should. i am 110% sure that whoever inventer the first magnifying scope was over the age of 50, or had eyesight problems to begin with.

Doc Highwall
06-14-2011, 12:26 AM
That would be the Cataract Scope manufacturer from the 1800's

I No Drive Cataract, I drive Rincon!

Three44s
06-14-2011, 12:51 AM
To have more options on an 1894 Marlin, I replaced the gold bead with the Lyman 17 Globe sight.

It wears a Williams appeture rear sight.

So far my favorite front insert in the globe sight is the square post. My next fav is the peep front insert.

Three 44s

303Guy
06-14-2011, 01:05 AM
Has anyone ever done a ring front in conjunction with an aperture rear? By ring I mean an oversize hollow bead, so to speak. Similar to but othersise different to target front tunnel sights (which are scary accurate to use).

The thought I've had regarding flat blades and 'U' notches is that if one gets the balance just right there will be a sort of elevation compensation for range as one focuses on the target itself. Not enough to make it an all-round long range sght but just a little to make it better than nothing.

Von Gruff
06-14-2011, 01:41 AM
I have a hood for my front sights that works for the 7x57 but not the 404. The front blade on the 7x57 is exactly half the height of the hood and gives me a blade in a circle with the hood giving a clear rim inside the aperture. That is good for accuracy work and and in good hunting light but can be a bit restrictive in failing light oir an aniumal without good contrast against the background. Usually hunt with a nekid front blade.

Von Gruff.

Bret4207
06-14-2011, 07:36 AM
This is one of those areas where personal preference and eyesight combined with target type rules. What works great on a 28" barrel with a 3" round bull for indoor shooting at 50 feet with 18 YOA eyes isn't necessarily going to work best for 50 YOA eyes on a 12" square bull at 100 yds from a 20" barrel. I'm about half blind and find, weirdly, that on some days a standard Mauser type inverted triangle front sight works great while a bead or post stink, all with peep sights. Other days a gold bead in dim woods works best. So I'm firmly in the "different strokes" category.

The Merit type apertures offer a good answer to some of the issue and so do fronts like the Lyman 17 with interchangeable inserts. Experiment and see what works best for you on the target of the day.

303Guy
06-14-2011, 07:52 AM
standard Mauser type inverted triangle front sightMy 1896 Cavalry Carbine has that type of sight. It forms interference patterns for my eys that makes it difficult to see. I can't focus on the front sight and don't shoot that way anyhow. I have good vision, just can't read without glasses although I can see at front sight distance just fine. I only want to shoot open sight with one or two particular guns because I don't want to change them.

Tatume
06-14-2011, 08:02 AM
Has anyone ever done a ring front in conjunction with an aperture rear? By ring I mean an oversize hollow bead, so to speak. Similar to but othersise different to target front tunnel sights (which are scary accurate to use).

Muzzleloading military/target rifles frequently have a front sight similar to what you describe. My Volunteer has a circular hood with a rectangular post in the center. The hood aligns concentrically with the (non-standard) aperture rear sight. The top of the post locates the target. It is a very accurate system, on game or targets.

Also, I have a front sight for the M1 that consists of a circular hood with a yellow plastic insert that has a hole in the center. The circular hood aligns with the rear aperture, and the target is placed in the hole. The field of view is tremendous, and I expect the sight would work well for hunting, though I have never tried it. Accuracy on targets is great. Unfortunately, its use takes the M1 out of the service rifle category and makes it a target rifle, so I don't use it any more. (Actually, I use a black rifle most of the time now anyway.)

Several people have made mention of the Merit adjustable aperture. Although I have one, I no longer use it for hunting or target shooting. I prefer to interchange apertures on the target field. In the woods I use a Williams 0.125" Twilight aperture. It works well for me.

Take care, Tom

Char-Gar
06-14-2011, 10:26 AM
It would be impossible to quantify such a rule. It would depend on the rifle, barrel length and use of the same (target, plinking or hunting).

You don't want the front sight so big it covers the target. All things being equal, which they never all, smaller apertures means smaller groups.

gnoahhh
06-14-2011, 10:50 AM
Count me as another proponent for Merit adjustable apertures.

Apart from providing a quick and accurate method of sighting, an aperture also provides a light focusing benefit also. The smaller the aperture, the more focused are the light beams hitting your eye, giving a sharper image of the front sight and the target. The trick is finding a balance between small enough to give best focusing (and hence better front sight/target definition which equals better bullet placement) and large enough to let enough light through to see what you're shooting at. That's why the smart hunter who is vision-challenged arms himself with the means to change aperture sizes in the field to optimize performance under changing conditions. An adjustable iris makes good sense to me in that regard.

Marble's used to offer front sight blades with gold colored apertures for use on Springfields, Savage 1899s and Model 1920s, and god-knows what else. I bought one recently but haven't installed it yet. I have my doubts as to it's effectiveness, but it is an interesting concept.

Canuck Bob
06-14-2011, 03:32 PM
This question is interesting for me because I'm considering a tang sight on a lever. I've used Williams or Lyman receiver sights for many years. In close or when darker I pull the aperture and shoot using the threaded ghost ring. My hunting Apertures are the smallest OD and then drilled out so they are only a bit smaller than the open hole on the rear of the aperture tunnel.

When I improvise a tang sight distance and use my sights with them closer to my eye the difference in perceived peep size is unnerving. It sure does sharpen the field of view.

How do folks feel about the replaceable insert target front sights for light duty field work?

Also the Beech Style Combo sight offers a front sight ring and post.

MBTcustom
06-14-2011, 08:52 PM
How do folks feel about the replaceable insert target front sights for light duty field work?
That,s a good question, I was thinking about going with a globe front sight myself.

Back to the original post, If there is no relationship between the front sight blade and the peep, is there something governing the size and shape of the ears on either side of the blade? We all know that they provide a level of protection to the blade but what about the way they are supposed to effect the sight picture for the shooter? ie. should they appear to be captured by the peep, should the tips be at 45degree angles to the tip of the blade, should the thickness be a certain percentage of the blade thickness in order to align the eye but not draw its attention?
The reason I asked the original question was to discover why some iron sights are just very easy to look through and seem to just naturally put the boolits where you tell 'em to go. I'm sure that we all have plenty of experience with sights that we have to struggle with, but I'm equally convinced that anyone here who has grown up shooting has found some sights that just work head and shoulders better for all around shooting than any other combination. Personally, I fell in love with peep sights the very first time I used them. By the same token, the very worst sights that I have ever used were the as issued ruger 10-22 sights. (Mind you, I love the rifle, but that big honkin front bead and more importantly, the way it fits in the rear notch, is shoddy, and its impossible for me to do precision work with it.) In comparison the winchester 290 had a very similar sight arrangement in that it had a round bead front sight and a half circle notch rear. The difference was that with the latter rifle, the front bead fit into the rear notch like your first-born in the arms of your wife, the bead was also just big enough to see clearly without straining but not so big that it was hard to divine the apex of the radius witch seamed to render bullet holes in paper with remarkable consistency. I could easily shoot sub MOA groups with the 290, but I had to use a scope with the 10-22 to achieve the same result.
Another lousy sight combination was found on my marlin 336 30-30. However my fathers vintage 336 .35 remington has a much better ratio.
Another example is the modern remington speedmaster .22 vs, the sights on the vintage rifle.
My wifes remington targetmaster single shot has very good ratio of front sight diameter to rear notch width.
In fact check out any modern sight setup on your average rifle and the sights are just slapped in there with no regard to fit or function. Remington is my favorite brand of firearms but they are guilty of this far more than others I have seen. They routinely put bead front sights that just float around in huge square notch rear sights, its like they got the memo that square sights are better than round sights for target shooting, and round bead sights are better for snap shooting in hunting conditions and they tried to split the difference.
In contrast, you pick up a vintage battle rifle like the no.4 mk1 and although the sights are clunky in comparison,.....they......just.....fit. There is no strain on the eyes, you look a through the sights and you just want to be precise! unfortunately, the precision that the sights promise is a check that most No4 mk1s cant cash.
I think that there is a tendency today of bypassing or modifying the iron sights almost as if its a forgone conclusion, but I have found no basic wisdom and rules of thumb that would help guide somone to a good combination. I have shot so many vintage rifles that had superb sights, I figure that back before people could afford to buy a crosshair scope from wal-mart, the gun manufacturers cared a lot more about the iron sights on their rifles, and it shows.
Any way thats the data-dump of what I was thinking when I asked the original question. It may be that It just comes down to individual preference/ trial and error, but you cant blame me for asking.

Three44s
06-14-2011, 09:38 PM
I think a lot has to do with personal preference and one's current vision circumstances.

But I believe much has to to with how a stock fits you ..... Ie. cheek weld to the sights whether they be telescopic or iron ........ conventional or appeture.

Consistent cheek weld most likely gives us fits without our realizing it more than is commonly thought.

If one shoots a gun a lot and does so well ........... we keep going back to that weapon.

If we have poor performance ........... Why go back?

We instead reach for the gun that produces.

303guy asked about a "hole" front sight ....... are you asking about an appeture front sight? I have not really used mine but an appeture front sight insert does come with the Lyman 17 globe front.

Also, there is one expressly for the Mosin Nagant rifles by another company ........

http://www.mojosights.com/SnapSights.html#

Three 44s

Von Gruff
06-14-2011, 10:36 PM
Also the Beech Style Combo sight offers a front sight ring and post.

I tried to google this sight but dont get a hit with the one you pictured. Have you got a link to them.

Von Gruff.

303Guy
06-15-2011, 12:21 AM
If there is no relationship between the front sight blade and the peep, ...Oh but I believe there is a relationship. It was a very good question - one I've pondered over too. Likewise the relationship between the 'U' size and the front blade width and the distance relationship between eye to rear sight and between the sights. The trick I think, is to record the parameters on those that work well - like I would think to do that! Mind you, I might now! Your new question is also very relevant and interesting and not so easy to answer (I think).

303Guy
06-15-2011, 12:27 AM
Three44s

Yes that's exactly what I was asking! Thank you.:drinks:

I've never seen or heard of such a thing before yet I thought about it and it exists! But does it work well? It could save my iron sight shooting career.:roll:

http://www.mojosights.com/images/SightCompWeb.jpg

Well shoot. I can experiment and find out for myself. I like the idea of the globe sight (with ring around it?) in conjuction with the 'ring' front sight. I could have some fun with sights.:Fire:

Longwood
06-15-2011, 02:30 AM
I tried to google this sight but dont get a hit with the one you pictured. Have you got a link to them.

Von Gruff.

When I was searching for a better front sight, I found those on ebay. I almost tried one and may yet if the period scope on the 45-70 keeps giving me trouble.
I know for sure that I would try one if I was using the rifle for both hunting and targets.

Longwood
06-15-2011, 02:54 AM
I tried to google this sight but dont get a hit with the one you pictured. Have you got a link to them.

Von Gruff.

Here is a link to one that is similar but expensive in my opinion.

http://www.brownells.com/.aspx/cid=0/k=globe/t=P/ksubmit=y/Products/All/search=globe

MBTcustom
06-15-2011, 06:33 AM
They shouldn't have given such a close-up photo, now I can make my own:lol::lol:
As far as the hole in the front sight goes, I have had a rifle that had a holy front sight like that, but the hole was too small and I hated it, it definitely did that thing where it draws the eye instead of helping to align it. That sight may have a big enough hole that it works better.
I have a friend at work that used to shoot competition small-bore rifle and he told me of a way to make a sight insert for a lyman or anshults globe front sight, that is very easy to look through. You make a disc of Plexiglas and counter-sink a hole in the middle of it and that provides a hazy ring that is just floating in space. It sounded like a cool concept so I made one, but I haven't tried it out yet.
Here she is.
http://i1120.photobucket.com/albums/l481/goodsteel/IMG_0676.jpg

Doc Highwall
06-15-2011, 10:34 AM
goodsteel, I have some sights like that, the countersink side is placed away from the shooter when looking through it.

The shaded part is affected by the thickness of the material and the angle of the countersink.

The bad problem of them is when they become all scratched up or they have moisture get on them they are hard to look through.

The last sight that 303guy posted the hollow lollipop works great as it does not block as much of the view as the aperture's that are supported by a horizontal bar on each side like the ones that Redfield and Lyman make.

frkelly74
06-15-2011, 11:26 AM
When I was in rifle club while I was still in High school I had a rifle set up with the lyman 17 front sight and the insert I used most was an orange plastic disk with a hole in the center that the 50 ft bullseye would just fit into. It worked very well for that but not for much of anything else. That was what most of my shooting was at that point so that worked out well for me. Prior to getting that I used the black aperature front sight and that works well if your eyes are young and sharp.

I had my m1917 and my 03A3 out together and found that the sights were easier to use on the 1917. Just seemed easier to look through. So when I got home I looked through my drills and found one that fit nicely in the 1917 sight and drilled the 03A3 sight out . I also put a slightly thicker blade in the front sight . Problem fixed.

Longwood
06-15-2011, 06:46 PM
I used a Lyman 17 on one of my Silhouette barrels and liked it a lot so when I bought my Thunderbolt, I decided to try one on it to go along with my new tang sight.
Money well spent in my opinion. I get a nice black, very clear, without the usual glare from the sun, front sight even in the desert sun and like that I can change apertures any time I like.
Right now it has a small circle in it. The rifle has a pretty long barrel so I may go with the bigger circle aperture or back to the blade that I had in it a while back.

NHlever
06-15-2011, 08:06 PM
When one is hunting, seeing the front sight is vital. Your eye wll take care of the rear sight if you let it. I like post, or ramp front sights that are .100, or so wide. I hunted a couple of years with a white 1/8" bead, and that worked very well on deer, and larger dark colored critters, but I eventually went back to the 3/32" bead as being more useable all around. Even the AO front sight doesn't work for me since the white stripe overpowers the blued ramp sight, and the white isn't wide enough for me to focus on quickly. I have also shot some very good groups on a good day with both the wide ramp, and the 3/32" bead. I have a bunch of different sized rear apertures, but usually use something around .100 or just screw it out in poor light. The Enfield front sight is a bit too narrow for my tastes, but it sure is an improvement over the Mauser sights!

Canuck Bob
06-15-2011, 11:31 PM
I tried to google this sight but dont get a hit with the one you pictured. Have you got a link to them.

Von Gruff.

http://www.montanavintagearms.com/combo_front.html

also

http://www.brownells.com/.aspx/pid=26062/Product/FOLDING_FRONT_SIGHT

I think Buffalo Arms might have one too. I think these are repros of sights sold by Lyman years ago, not certain though.

Von Gruff
06-16-2011, 12:39 AM
http://www.montanavintagearms.com/combo_front.html

also

http://www.brownells.com/.aspx/pid=26062/Product/FOLDING_FRONT_SIGHT

I think Buffalo Arms might have one too. I think these are repros of sights sold by Lyman years ago, not certain though.

They look to be a good combination and I supose it has a detent to hold it in either position. I have the Recnagel Masterpiece front ramp an my rifles so that dovetail fitting would not work but they certainly offer a good option.

Von Gruff

MBTcustom
06-16-2011, 01:23 AM
I like that small pinhead configuration! I still think I could make it and save a lot of money. Thats a good design though.

Canuck Bob
06-16-2011, 04:57 PM
They look to be a good combination and I suppose it has a detent to hold it in either position. I have the Recnagel Masterpiece front ramp an my rifles so that dovetail fitting would not work but they certainly offer a good option.

Von Gruff

Some of the Recnagel products look excellent as well. They make some very nice and unique gun hardware.

I'm researching if the Combo sight will fit my Winoku 92 right now.